Applying the Reference Condition Approach to bioassessment of Cape Breton Island streams

The reference condition approach (RCA) to bioassessment assesses the effect of human activity on ecosystems relative to sites that are relatively unexposed to such activity. This study uses the RCA to characterize the nature of relatively pristine streams on Cape Breton Island, Nova Scotia as a comparison to assess sites that have various degrees and types of exposure to human activities, including sites that have been remediated from acid mine drainage related to coal mining. RCA models consisted of general linear models with environmental characteristics of reference sites as the predictor variables and biotic indices as the response variables. Findings suggest that the diverse natural environments of the island correlate poorly with stream biota (macroinvertebrates and fishes). Further research should be completed to enhance these predictive models. Results also show that healthy biological communities can be re-established at remediated sites but it may take a few years for full recovery. This baseline biological data will be used to track the progression of remediation programs in Cape Breton